---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-23-003595"
form_type: "8-K"
ticker: "APTOF"
cik: "0000882361"
company_name: "Aptose Biosciences Inc."
filed_at: "2023-05-26T23:59:59+00:00"
generated_at: "2026-06-14T13:46:59.218514+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Aptose Biosciences enters $25M committed equity facility with Keystone Capital Partners

## Summary
- Up to $25M in common shares may be sold over 24 months at Company's discretion.
- 377,336 commitment shares issued to Keystone as consideration for the facility.
- Fixed purchases limited to 50,000 shares/day at price >= $0.25; VWAP purchases allowed.
- Net proceeds to be used for working capital and general corporate purposes.
- TSX conditionally approved; facility subject to Nasdaq Exchange Cap and other conditions.

## SEC filing metadata
- accession: 0001171843-23-003595
- form_type: 8-K
- ticker: APTOF
- cik: 0000882361
- company_name: Aptose Biosciences Inc.
- filed_at: 2023-05-26T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 1.01, 3.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/882361/000117184323003595/0001171843-23-003595-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/882361/000117184323003595/f8k_052523.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-23-003595
- JSON: https://secwatch.observer/filing/0001171843-23-003595.json
- Plain text: https://secwatch.observer/filing/0001171843-23-003595.txt

## Key facts
- Material Agreements
  Aptose Biosciences Inc. entered into Registration Rights Agreement with Keystone Capital Partners, LLC (effective 2023-05-25).
  - Action: entry
  - Counterparty: Keystone Capital Partners, LLC
  - Effective: 2023-05-25
  source text: Additionally, on May 25, 2023, the Company and Keystone entered into a registration rights agreement (the “ Registration Rights Agreement ”), pursuant to which the Company agreed to file a registration statement with the United States Securities and Exchange Commission (“ SEC ”) covering the resale of Common Shares that are issued to Keystone under the Purchase Agreement.
  evidence_url: https://www.sec.gov/Archives/edgar/data/882361/000117184323003595/0001171843-23-003595-index.htm
- Material Agreements
  Aptose Biosciences Inc. entered into Purchase Agreement with Keystone Capital Partners, LLC valued at $25,000,000 (effective 2023-05-25).
  - Action: entry
  - Agreement: equity purchase
  - Counterparty: Keystone Capital Partners, LLC
  - Value: $25,000,000
  - Effective: 2023-05-25
  source text: On May 25, 2023, Aptose Biosciences Inc. (the “ Company ”) and Keystone Capital Partners, LLC (“ Keystone ”), entered into a common share purchase agreement (the “ Purchase Agreement ”), which provides that subject to the terms and conditions set forth therein, the Company may sell to Keystone up to the lesser of (i) $25,000,000 of the Company’s common shares
  evidence_url: https://www.sec.gov/Archives/edgar/data/882361/000117184323003595/0001171843-23-003595-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.